Challenge for the construction of
the initial lipid bilayer is the main problem in setting up a
simulation for membrane proteins considering protein dynamics,
folding, and the mechanism of action. Almost all membrane models
used in molecular dynamics simulations are usually composed of only
one type of phospholipids molecule that is quite far from the native
biological state, because biological membranes contain various types
of lipids. Moreover, the asymmetry of lipid composition of the lipid
bilayer is functionally important.

MemBuilder server prepares
the initial configuration of a membrane model composed of different
phospholipid molecules. This server is also dedicated to determine
the lipid composition of each monolayer to support the asymmetry of
the membrane bilayer.

Cholesterol is built
using HyperChem and optimized using quantum calculations with Gaussian
03 at the Hartree-Fock level employing the 6-311G* basis set.
Cholesterol topology file is built using PRODRG web server.